Motor in bad shape - is there hope?

Sounds like good advice to me... is this something I can get at the LHS or do some of the sponsored vendors sell rods that are already the right length and thread? I suppose I could just get a grade 8.8 threaded rod and cut it to size, but that's extra work, heheh...

Buy grade 8.8 threaded rod, and make your own, buy from a vendor, or check out my profile. Use nylon locking nuts and lock tite on the threads in the case.
 
The rings you have right now are worn out. The heavy carbon build up going down the sides of the piston are the telltale sign. They are cheap and easy to replace.
Do not re-use the piston pin clips. If and when you order new rings and a base gasket, order new piston pin clips as well. I have seen them called "G" rings or "G" clips in the exploded parts lists at various vendor sites.
Use pre-mix oil as an assembly lube wherever 2 metal parts may touch each other (but not on the head gasket).
An alternative to the highly recommended Copper Kote that is also very good (and you may all ready have around) is aluminum spray paint. Be sure that is does in fact have aluminum powder in it. Most do, some do not. Same procedure applies. Two coats on both sides, let dry thoroughly between coats. Install dry.

All good...Have used aluminum paint before myself with good results, I just like Copper Kote, and if you ever see it or use it you will understand. A added feature to CK is it has an adhesive and sticks quite well to both cylinder and head...Don't forget to mill your head before instillation. Used wrist pin retainers ("G" clips) can cause headaches down the road. I use them over again, I know what I'm doing too, but it's a chance.
 
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Just a side note, I don't recommend using a ball hone in a two stroke cylinder as the abrasive balls can bugger up the edges of the ports. A bar hone (umbrella type) is the preferred hone for two strokes.
 
Just a side note, I don't recommend using a ball hone in a two stroke cylinder as the abrasive balls can bugger up the edges of the ports. A bar hone (umbrella type) is the preferred hone for two strokes.

So true.. Was pointing out the types and process. I have the umbrella type.
 
Just a side note, I don't recommend using a ball hone in a two stroke cylinder as the abrasive balls can bugger up the edges of the ports. A bar hone (umbrella type) is the preferred hone for two strokes.

Exactly.

Spray the hone stones with wd-40 before inserting into the cylinder.

Also, any time that the hone is in motion inside the cylinder, constantly spray wd-40 in there.

And it shouldn't take more than a few seconds, to break the glaze in that cylinder.
 
I've been able to find new piston rings and bottom gaskets on several vendors, but I'm having a hard time finding replacement "G" rings for the piston pin. Is it possible to reuse the old ones?

Edit Cool - found some of the clips on pirate cycles.
 
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Thanks for all the info on cylinder honing - it doesn't sound as daunting as I thought at first, but I still hope I can get away without doing it this time around. Unless this is a terrible idea, I am going to try my luck without honing the cylinder and just replace the bottom gasket and piston rings as well as using some of that CopperCote spray to seal the aluminum head gasket. At this point I am under the impression that most of my power loss stemmed from the head gasket leak. For good measure, I will also replace the stock rods with grade 8.8 rods and nylon lock nuts as suggested earlier.

Much obliged, everybody! I'll follow up as the repair progresses.
 
I've been able to find new piston rings and bottom gaskets on several vendors, but I'm having a hard time finding replacement "G" rings for the piston pin. Is it possible to reuse the old ones?

Edit Cool - found some of the clips on pirate cycles.

For a one word answer to your question..."YES"

I have never replaced the wrist pin clips "G" rings on any engine I've ever had. I break down everyone of them out of the box to upgrade the studs. The trick, if you want to call it that is to use a good pair of needle nose pliers, grip the tab and as you rotate the tab inward to the center, slowly pull at the same time..do not force. Not saying that the clip won't come out while running but I've reused clips about 10 times (different engines) without one incident. Unless necessary, remove only one and slide the wrist pin out.
 
My first engine kit I used the G clips over again and about two miles down the road it got pretty ruff and then it would not start after I parked it. turns out that it "ate" the clips and scored the piston so badly I replaced the engine. I got a new engine on sale at zipp for about eighty bucks and its been working grate since then. The next time I rebuilt the motor I got new clips and new low end gasket, plus a thinner head gasket from S.B.P. It just ticks over like a watch now.

mike
 
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